We report a case of venous oxygen embolism in a 33-yr-old healthy woman after irrigation of a vulvar abscess with 25 ml of 3% hydrogen peroxide. Venous oxygen embolism was diagnosed by the development of sudden hypoxia associated with a decrease in end-tidal carbon dioxide concentration from 5.3 kPa to 3.2 kPa, and a 'mill-wheel' sound on cardiac auscultation soon after injection of the solution. The patient responded to corrective treatment including the Trendelenburg position and 100% oxygen. She made an uneventful recovery. We discuss the possible causative mechanism of this embolism, the different diagnostic methods, and the controversial aspects of available treatments. We emphasize that hydrogen peroxide is a dangerous and unsuitable agent for routine wound irrigation and debridement.